Improvement in saw-mills



UNITED STATES PATENT OFFICE.

E. P. IRONS, OF BALTIMORE, MARYLAND.

IMPROVEMENT IN SAW-MILLS.

Specification forming part of Letters Patent No. 55,497. dated June 12,1866.

To all whom it may concern:

Be it known that I, EDWARD l?. IRONS, of Baltimore, in the county ofBaltimore and State of Maryland, have invented certain new and usefulImprovements in Portable Upright Saw-Mills, and I do hereby declare thefollowing to be a full, clear, and exact description thereof, referencebeing had to the anneXed drawings, making partof this specification, inwhich Figure 'l is a plan or top view of my sawmill. Fig. 2 is a sideelevation thereof. Fig. 3 is an end elevation, and Figs. 4t and 5 showparts in detail. A

Similar letters of reference indicate corresponding parts in the severalfigures.

A A are the tilnberbeds of my saw-mill, having the uprights B, B', andO, with their cross-ties D, D, and E firmly braced to them, the wholeforming a frame-work ofthe strength necessary to insure stability whilethe saw is performing its office.

The journal-boxes F F on the nprights B' and G support the bearings ofthe shaft G. This shaft has motion given it by a belt from thedriving-power around the fast pulley a, which belt may be shipped by anycommon device to the loose pulley b on the same shaft when it is desiredto stop the work of the saw without checking the driving power or force.On one end of this shaft G is a crank-plate, H, giving motion, throughthe connecting-rod or pitman c, to the walking-beam l, which vibrates ona center in the journal-box d, bolted to the lower end ofthe upright B.Another walking-beam, I', similar to the first, is hung at thejournalboxd', attached to the upper end of the upright B'. The ends of thesewalking-beams are arcs of circles having the journals d d' for theircenters. From near each end of the walkingbeams, where they are attachedby bolts e, eX- tend tension-rodsff' toward the opposite ends ofthebeams,wherethey are hooked into twisted wire cords or bands g g g' g',which pass over the circular ends ofthe walking-beams and fall intogrooves therein like the groove in a sheave or pulley. The wire cords orbands g g are attached one to the upper and the other to the lower endof an upright saw, the blade of which is tangent to the curves on theends of both walking-beams, and is extended vertically between them. Theother cords or bands g g' are attached t0 tension or straining rods hh', one, h, extending down from the upper walkin g-beam, I', andterminating in a screw, and the other, h', extending up from the lowerbeam, I, and having a swivel turn-buckle, X, which takes the screw onthe upper strainingrod, 7L. This arrangement allows the beams I I to bemade much lighter than they could otherwise be, furnishes the means ofstraining the saw as tight as may be desired by turnin g the turn-buckle, while the iiexibility of the wire cords or bands over the endsof the beams allows these to vibrate on their centers with perfectfreedom and always parallel.

Spiral springs, or some equivalent device, are attached to thewalking-beams, as shown distinctly in Fig. 3, for the purpose ofgradually checking momentum and preventing anything like jerking orpounding while the saw is in rapid motion.

A connecting-rod, z', is jointed to the lower walking-beam, I, and atits upper end is linked to the end K of the bell-crank lever K K',having its fulcrum on the feed-shaft L, (shown in red in Fig. 2.)

The arm K' of the bell-crank in its crossseetion is of the form of across, or T-shaped, to give it sti'ness and make it light, and isreceived by an opening in the end of the con necting-rod 7c, which itmovesin its vibration.

This opening is armed by steel plates m, Fig. l

5, made adjustable to con'ipensate for wear and to take up lost motion.The other end of the connecting-rod It' is jointed to the lever M,having its fulcrum at l on the arm N, attached to the upright B' nearits upper end.

The lever M carries at its lower end and gives, by its vibration,reciprocating motion to the feed-hand m, which, in turn, pushes roundthe rag-wheel O, fast on the feed-shaft L, a detent or pawl, n,servinglto keep the rag-wheel O from turning back after being moved bythe feedhand.

The shaft L has its bearings on both the bedtimbers AA ofthe mill, andcarries two pinions, (shown in red in Figs. 2 and 3,) which pinions takeinto ranks on the under side of the rails of the log-carriage, and bytheir revolution cause the log-carriage to be moved, so as to feed thelog to the saw.

The steel-armed end of the connecting-rod 7c can be dropped down uponthe ribbed arm K of the bell-crank, so as to be near the shaft L, or itcan be lifted up to the extreme end of K, by means of a cord or chainunder the control of the mill-tender, the distance from the shaft L thatitis operated by the arm K of the bell-crank, regulating the amount offeed at each stroke of the same. Thus, if alog of soft wood be underoperation, the connecting-rod is lifted up toward the end of the arm Kto give the longest desirable stroke to the feedhand of the ratchetthrough the leverM; and now, ifa hard, flinty knot comes against thesaw, it will be expedient to lessen the feed, which is done immediatelyby dropping the armed end of the connecting-rod la down on the arm K asnear the shaft L as may be necessary to cause the feed-hand to move therag-wheel a sufficiently short distance.

On the shaft Gis a small pulley, l. A belt from this passes looselyaround the pulley Q, on the feed-shaft L. A bent lever, R, having itsfulcrum on the feed-shaft L, carries at one end a friction-pulley orrider, S, and at the other end has a cord or chainT, to govern itsmovement, which is carried in a direction to be under the control of themilltender. The cord may be attached also by hooks, or theirequivalents, to the detenta and the feedhand on, so that when it isdesired to run the log back from the sawapull upon the cord T will liftthe feed-hand and pa-wl free from the ragwheel, and will also raise thelower end of the bent lever R, forcing the rider S to tighten the beltaround the pulleys P and Q, so that motion will be given to thefeed-shaft in a direction contrary to that which it had when moved bythe ratchet. The arrows indicate the direction of the revolutions whilethe log-earriage is being run back from the saw.

The log-carriage can be arranged to disengage the feed-hand and pawl andcause itself to be run back at the conclusion of every cut by any of thecommon and known devices for that purpose.

To the cross-ties D D, connecting the upper ends of the uprights B B',and to the cross-tie connecting the ends of the bedtimbers A A, aresecured by bolts the guides U U for the slides at each end of the saw.The end of the saw is embraced between two plates, forming a stirrup, qq, through which and the saw screw-bolts r r pass and are secured bynuts. The wire cord g is lrmly attached to the stir rup a short distancefrom the end of the saw.

To one of the plates q, (and forming, if necessary, one piece with it,)are attached the jams t t, embracing the edges of the guides t, andhaving gibs u u, adjustable by means of setscrews,'so that they mayslide freely yet be perfectly tight upon the guides U.

Having thus fully described my invention, what I claim therein as new,and desire to secure by Letters Patent, is

l. The described mode of connecting the elastic saw-bands g g to thewalking-beam by rods j ff, attached at points e at the opposite ends ofthe beam from that upon which the said bands g y', are lapped,substantially as de scribed.

2. The manner, substantially as herein described, of attaching theflexible wire cords or bands to the ends of the saw by means of thestirrups g, in combination with the jaws t t, the adjustable gibs a a,and guides U, the parts arranged and operatin g substantially in themanner and for the purpose set forth.

3. The combination of the connecting-rods @bell-crank K K', graduatingconnecting-rod InleverM, feed-hand m, rag-wheel O, and shaft L withpinions and racks, arranged and operating substantially as and for thepurpose set forth.

4. The manner of graduating the length of the cut or feed by means ofthe graduating connecting-rod 7c, moving up and down on the arm K' ofthe bell-crank lever, so as to be moved a long or short distance, forthe purpose and substantially in the manner set forth.

5. rlhe combination of the adjustable steel arming plates a: with aconnecting-rod, 7c, ar-

ranged and operating as herein set forth, for the purpose ofcompensating for wear and allowing lost motion to be readily taken up,as

